Symbiote

Obviously based off venom) This happens in a fictional superhero universe (That you can make the lore for) and you are a normal civilian(You make your character) and your just walking through the forest but then a black goo buries itself into its bag and you think nothing of it thinking you were seeing things but little did you know it would change your life(You can pick the powers it gives what and if your a good guy or bad guy and you can pick what it transforms you into) Have fun :)